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1.
Sci Rep ; 13(1): 1591, 2023 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-36709214

RESUMEN

Traditionally, smear microscopy has been used to estimate bacillary burden in order to assess infectiousness in tuberculosis (TB) patients. Since Xpert MTB assays might replace smear microscopy as the first-line diagnostic test for pulmonary tuberculosis, an alternative measure of bacillary load that correlates with smear positivity is needed. This study assessed the correlation between CT (with and without normalization), smear status, culture time-to-positivity (TTP), and clinical factors in patients with Xpert ultra positive sputum during a four-year period. A cut-off CT value for smear positivity was also estimated. 204 samples were included. Strong correlation between both Xpert Ultra CT values (raw and normalized) and smear status was obtained (r = 0.78 and - 0.79, respectively). The association between Raw-CT and TTP was weaker than normalized-CT (N-CT) and TTP (r = 0.50 and r = - 0.70, respectively). A Raw-CT cut-off value of 21.4 was identified with 85.7% (95% CI 65.4-95) sensitivity and 92.9% (95% CI 84.3-96.9) specificity. A N-CT cut-off value of 5.2 yielded a sensitivity of 94.3% (95% CI 86.2-97.8) and specificity of 85.7% (95% CI 65.4-95). Our study demonstrates that Xpert Ultra CT value correlates well with other measures of bacillary load such as smear status or TTP. The correlation with TTP is stronger when the CT value is normalized using the internal control. The proposed N-CT cut-off value of 5.2 shows a better sensitivity than the Raw-CT when predicting smear positive status.


Asunto(s)
Bacillus , Lacticaseibacillus casei , Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Mycobacterium tuberculosis/genética , Esputo , Sensibilidad y Especificidad , Tuberculosis Pulmonar/diagnóstico por imagen , Firmicutes , Tomografía Computarizada por Rayos X
2.
Transplantation ; 106(11): e476-e487, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35859270

RESUMEN

BACKGROUND: Few studies have described the clinical impact of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in renal transplant recipients (RTRs) in the context of omicron variant and the third vaccine dose. Antibody titer has been tried to relate to the prediction of outcomes related to SARS-CoV-2, but it results controversially in these populations. METHODS: All patients with positive SARS-CoV-2 polymerase chain reaction followed at a RTRs reference center from March 15, 2020, to March 15, 2022, were considered for analysis. Cases were analyzed by vaccination status. Breakthrough cases were then analyzed by nonantibodies (<20 arbitrary unit [AU]/mL), low (20-100 AU/mL), and high antibody titers (>100 AU/mL) against SARS-CoV-2 spike protein. Outcomes included pneumonia and mortality. We used logistic regression multivariable to assess for confounders. RESULTS: Among 186 RTRs with coronavirus disease 2019, 50.5% (n = 94) were vaccinated versus 49.5% (n = 92) unvaccinated. Of the vaccinated patients, 67.02% developed a high antibody titer (>100 AU/mL) but 14.89% achieved a low antibody titer and 18.08% nonantibodies. Pneumonia-free survival (day 20) was 95% in high antibody titer but 40% in unvaccinated RTRs. Survival in RTRs at day 60 was similar in the unvaccinated group compared with nonantibodies breakthrough cases (82%) but 92% in the low antibody titer group (relative risk, 0.027; 95% confidence interval, 0.002-0.479; P = 0.014). Only patients with >100 AU/mL showed a 100% survival on day 60 postinfection. CONCLUSIONS: Vaccinated RTRs who achieve at least a low antibody titer (>20 AU/mL) had better results in terms of pneumonia and mortality than unvaccinated RTRs. Antibody titer >100 AU/mL associate with even better results than patients with lower antibody titers.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Trasplante de Riñón , Humanos , Anticuerpos Antivirales , COVID-19/prevención & control , SARS-CoV-2 , Receptores de Trasplantes , Resultado del Tratamiento , Vacunación
3.
Rev Gastroenterol Mex (Engl Ed) ; 84(4): 427-433, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30292584

RESUMEN

INTRODUCTION AND OBJECTIVE: Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. MATERIALS AND METHODS: A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. RESULTS: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n=29,253) was 3.69 cases×1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n=4,152), it was 26x1,000 (95% CI: 22.6 to 29.4). CONCLUSIONS: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69×1,000, and in the children that underwent endoscopy, it was 26×1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America.


Asunto(s)
Esofagitis Eosinofílica/epidemiología , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Gastroenterología , Hospitales Especializados , Humanos , Lactante , América Latina/epidemiología , Masculino , Prevalencia
4.
J Endocrinol Invest ; 31(5): 416-21, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18560259

RESUMEN

Previous in vitro studies suggest that the anti-resorptive effect of raloxifene might be mediated by changes in several cytokines involved in the bone remodeling process. In this context, the osteoprotegerin (OPG)- receptor activator of NF kappa B ligand (RANKL) system is considered a key component in the osteoclastogenesis regulation. The aim of this study was to determine the effects of raloxifene treatment on serum concentrations of OPG, receptor RANKL and its relationship with biochemical markers of bone turnover and bone mineral density (BMD) in previously untreated women with post-menopausal osteoporosis. We selected 47 post-menopausal women (mean age 63+/-7 yr) with densitometric criteria of osteoporosis. We determined at baseline, 3, 6, and 12 months anthropometric parameters, biochemical markers of bone turnover, serum levels of 25(OH) D, serum levels of OPG and RANKL. BMD (dual-energy x-ray absorptiometry) in lumbar spine (LS) femoral neck and total hip was measured at baseline and 12 months after raloxifene (60 mg/day) treatment. Serum levels of OPG decreased in the 3rd and 6th month of treatment (p<0.001) and returned to basal levels in the 12th month. There was a significant decrease of RANKL levels and OPG/RANKL ratio after 1 yr of raloxifene treatment. In addition, BMD in LS increased significantly (2.5%) in the 12th month of treatment (p=0.031). Finally, the biochemical markers of bone turnover (total alkaline phosphatase, bone alkaline phosphatase, osteocalcin, tartrate-resistant acid phosphatase, urine cross-linked carboxi-terminal telopeptide of type I collagen) decreased significantly from the 3rd month of treatment. In conclusion, our results support the hypothesis that raloxifene may inhibit osteoclast activity, at least partly modulating the OPG-RANKL system.


Asunto(s)
Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoprotegerina/sangre , Ligando RANK/sangre , Clorhidrato de Raloxifeno/uso terapéutico , Anciano , Conservadores de la Densidad Ósea/uso terapéutico , Calcio/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Clorhidrato de Raloxifeno/administración & dosificación , Vitamina D/administración & dosificación
5.
J Matern Fetal Neonatal Med ; 30(10): 1139-1146, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27334556

RESUMEN

OBJECTIVES: To describe a case diagnosed with intracranial teratoma in week 32 of gestation, as well as review of the literature in order to discern the appropriate treatment method and general prognosis of this anomaly. METHODS: A literature search was performed on the prenatal diagnosis of congenital intracranial teratomas in MEDLINE, EMBASE, Cochrane library data bases. Evaluated in this review are parameters such as time of prenatal diagnosis, associated pathology, size of tumors, method of terminating pregnancy, perinatal outcome and histological study of the tumor. RESULTS: A total of 49 cases were found, of which 12 were finished gestation, 28 cesarean section was performed and only nine had vaginal delivery. All died in the neonatal period except in three cases with intrauterine death after diagnosis. CONCLUSION: As the incidence of intracranial immature teratomas is very low and the prognosis is poor, their prenatal diagnosis and obstetric management present a great challenge for the planning of a follow-up and treatment of the disease in accordance with the preferences of the parents.


Asunto(s)
Neoplasias Encefálicas/congénito , Enfermedades Fetales/patología , Teratoma/congénito , Adulto , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Cesárea , Resultado Fatal , Femenino , Enfermedades Fetales/diagnóstico por imagen , Humanos , Recién Nacido , Embarazo , Teratoma/diagnóstico por imagen , Teratoma/patología , Teratoma/cirugía , Ultrasonografía Prenatal
6.
Transplant Proc ; 48(9): 2947-2949, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27932114

RESUMEN

BACKGROUND: The aim of this study was to determine the distribution of uridine diphosphate-glucuronosyltransferase 1A9 (UGT1A9) promoter region T-275A and C-2152T single-nucleotide polymorphisms (SNPs) in stable transplant patients and to investigate the impact of these SNPs on the evolution of this population after 10 years of follow-up. METHODS: White renal transplant recipients (n = 873) were studied. The median time of follow-up was 91.8 months (P25-75 46-146). Amplification with specific "primers" to delimit the study area was performed for each polymorphism. Amplification was performed with the use of real-time polymerase chain reaction. RESULTS: T-275A promoter mutation was detected in 13% of patients and C-2152T in 12% of patients. Survival analysis was performed on 873 renal transplants, carried out between 2004 and 2013. We found a higher frequency of death from cancer among polymorphism carriers (P = .001). CONCLUSIONS: It appears that carriers of T-275A and C-2152T SNPs of the UGT1A9 gene promoter region show a greater incidence of death from cancer, with a significantly higher cumulative incidence of death from gastrointestinal tumors.


Asunto(s)
Neoplasias del Sistema Digestivo/genética , Glucuronosiltransferasa/genética , Trasplante de Riñón , Complicaciones Posoperatorias/genética , Regiones Promotoras Genéticas/genética , Adulto , Cartilla de ADN , Neoplasias del Sistema Digestivo/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Complicaciones Posoperatorias/mortalidad , Reacción en Cadena en Tiempo Real de la Polimerasa , UDP Glucuronosiltransferasa 1A9 , Población Blanca/genética
7.
Int J Biochem Cell Biol ; 33(12): 1227-38, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11606259

RESUMEN

We have studied the growth rate, nucleic-acid concentration, protein-accumulation rate (K(G)), and several other parameters relating to protein turnover, such as the protein-synthesis (K(S)), and protein-degradation rates (K(D)), protein-synthesis capacity (C(S)), protein-synthesis efficiency (K(RNA)), protein-synthesis rate per DNA unit (K(DNA)) and protein-retention efficiency (PRE), in the white muscle of rainbow trout during development. Both growth rate and relative food intake decreased significantly with age and weight, as did the food-efficiency ratio (FER) and protein-efficiency ratio (PER). Although absolute RNA and DNA contents increased with age, their relative concentrations decreased. The RNA/DNA ratio increased sharply from 14 to 28 weeks but afterwards decreased towards initial values. Hypertrophy increased rapidly to the 28-week stage but henceforth increased much more slowly. Hyperplasia, on the other hand, continued to increase linearly, resulting in a significant four- to fivefold predominance in this type of growth at the end of the 96-week experimental period. K(G) decreased significantly with age, as did K(S), and C(S), whereas at the 14-week stage, K(D) was significantly lower than at other ages. K(RNA) increased until 28 weeks. K(DNA) increased significantly in juvenile fish compared to both fingerlings and adults, where it showed similar lower values. PRE remained high at all ages.


Asunto(s)
Fibras Musculares de Contracción Rápida/fisiología , Biosíntesis de Proteínas , Factores de Edad , Animales , Oncorhynchus mykiss , ARN/metabolismo , Factores de Tiempo
8.
Int J Biochem Cell Biol ; 33(8): 785-96, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11404182

RESUMEN

Little is known about the way in which carnivorous fish such as salmonids mobilise and metabolise dietary carbohydrates, which are essential to lipid metabolism. Thus we have studied changes caused by the absence of dietary carbohydrates to the kinetics and molecular behaviour of the four cellular NADPH-production systems [glucose 6-phosphate dehydrogenase (G6PDH); 6-phosphogluconate dehydrogenase (6PGDH); malic enzyme (ME); and isocitrate dehydrogenase NADP-dependent (NADP-IDH)] in the liver and adipose tissue of rainbow trout (Oncorhynchus mykiss). We used spectrophotometry to study enzyme kinetics and nucleic acid concentrations, and immunoblot analysis to determine specific protein concentrations. The absence of carbohydrate reduced specific enzyme activity, maximum rate and catalytic efficiency by almost 65% in G6PDH and 6PGDH, by more than 50% in ME, and by almost 25% in NADP-IDH but caused no significant changes in the K(m) values or activity ratios in any of these hepatic enzymes. Molecular analysis clearly showed that this kinetic behaviour reflected concomitant changes in intracellular enzyme concentrations, produced by protein-induction/repression processes rather than changes in the activity of pre-existing enzymes. We conclude that the absence of carbohydrates significantly reduces intracellular concentrations of G6PDH, ME and NADP-IDH in trout liver in percentages similar to those recorded for enzyme activity. We found no such variations in the concentrations of any of these enzymes in adipose tissue and no change in the levels of their activity, suggesting that the liver and adipose tissues are subject to different regulation systems with regard to carbohydrates and play distinct roles in lipid metabolism.


Asunto(s)
Tejido Adiposo/enzimología , Carbohidratos de la Dieta/administración & dosificación , Hígado/enzimología , NADP/biosíntesis , Oncorhynchus mykiss/metabolismo , Animales , Carbohidratos de la Dieta/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Immunoblotting , Isocitrato Deshidrogenasa/metabolismo , Cinética , Malato Deshidrogenasa/metabolismo , Fosfogluconato Deshidrogenasa/metabolismo
9.
Int J Biochem Cell Biol ; 30(1): 55-63, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9678961

RESUMEN

In fish, metabolic changes and qualitative responses during different nutritional situations are highly controversial in the scientific literature, and for this reason the objective of this work has been to probe deeper into the adaptive behaviour of two important amino acid-metabolising enzymes, glutamate dehydrogenase (GDH) and alanine aminotransferase (AAT) of liver and kidney in trout. In the present study, we examined the long-term effects of endogenous or exogenous proteins--generated, respectively, by a prolonged starvation or by feeding a high-protein diet--on the kinetics of liver and kidney GDH and AAT. Feeding on a high-protein diet significantly increased the liver (100%) and kidney (49%) GDH Vmax and catalytic efficiency; the same kinetic parameters of AAT increased by 65% only in the liver enzyme, without changing the Km and activity ratio values. Starvation registered a significant increase of both enzymes, Vmax and catalytic efficiency in the liver, but activity was unaltered in the kidney. In addition, no significant changes were found in the Km or activity ratio. All enzyme kinetics showed a Michaelian behaviour without any evidence of sigmoidicity. The experimental results show strong adaptive responses in the kinetic behaviour of the enzymes of both tissues. With the exception of renal AAT, the remainder of the enzymes presented a marked influence in their kinetic parameters by an excess of protein. The results are discussed in terms of the possible adaptive role of enzyme kinetics to amino acid availability.


Asunto(s)
Alanina Transaminasa/metabolismo , Carbohidratos de la Dieta/farmacocinética , Proteínas en la Dieta/farmacocinética , Glutamato Deshidrogenasa/metabolismo , Riñón/enzimología , Hígado/enzimología , Oncorhynchus mykiss/metabolismo , Inanición , Adaptación Fisiológica , Animales , Peso Corporal/fisiología , Simulación por Computador , Ingestión de Alimentos/fisiología , Modelos Biológicos , Especificidad por Sustrato
10.
Physiol Behav ; 55(6): 1135-6, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8047581

RESUMEN

This paper describes an easy-to-make, low-cost demand feeder. The electromechanical design ensures a single-pellet delivery for each demand. The feeder, activated by a fish pressing a bar, is driven by a solenoid. A variety of pellet shapes and sizes can be used, offering broad experimental versatility. The feeder is also suitable for microcomputer control.


Asunto(s)
Conducta Apetitiva/fisiología , Conducta Alimentaria/fisiología , Peces/fisiología , Microcomputadores , Psicofisiología/instrumentación , Animales , Diseño de Equipo
11.
J Physiol Biochem ; 56(3): 275-82, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11198164

RESUMEN

Those interested in the design and manufacture of feeds for intensive fish farming face the basic concern of formulating mixtures for the best yield at the lowest costs. Of the macronutrients in the feed, protein has and continues to receive special consideration because fish present high and specific needs for this constituent. Traditionally, protein has been supplied primarily by fish meals. This paper presents a synthesis of the efforts made and the lines explored to achieve an effective reduction of the amount of fish meal in the feeds for fish, following two strategies: reduction of the protein in the feeds and the use of new raw materials to replace fish meal.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Acuicultura/métodos , Proteínas en la Dieta/farmacología , Peces , Animales , Ingestión de Energía/fisiología
13.
Vet Parasitol ; 186(3-4): 415-24, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22137350

RESUMEN

Bluetongue virus is transmitted by Culicoides biting midges (Diptera: Ceratopogonidae). Culicoides associated with livestock were captured using CDC blacklight traps at three BTV-infected farms in Basque Country between November 2007 and December 2008. Twenty-seven and nineteen Culicoides species were collected in outdoor and indoor habitats respectively. Indoor insect community represented 86.1% of the whole captured individual biting midges. Culicoides obsoletus/Culicoides scoticus (two sibling species of the Obsoletus complex) were dominant throughout all months and sexes with maximum phenological peaks in November 2007 and June-July 2008. Culicoides lupicaris was the second most dominant species followed by Culicoides pulicaris (both species of the Pulicaris complex). Few specimens of Culicoides imicola, the principal Afro-Mediterranean vector of BTV, as well as four new species recorded for the Iberian Peninsula, were also collected. BTV was detected by RT-PCR from pools of C. obsoletus/C. scoticus, C. lupicaris and C. pulicaris parous females. DL-Lactic acid significantly attracted more C. obsoletus/C. scoticus females and males, C. lupicaris females, C. pulicaris females and Culicoides punctatus females and males; whereas acetone increased only the captures of Culicoides achrayi.


Asunto(s)
Virus de la Lengua Azul/fisiología , Ceratopogonidae/fisiología , Ceratopogonidae/virología , Animales , Ceratopogonidae/clasificación , Ceratopogonidae/genética , Femenino , Masculino , España
14.
Nefrologia ; 32(3): 287-94, 2012 May 14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-22508145

RESUMEN

The frequency of pregnancy in women on dialysis is extremely low, but the percentage of successful pregnancies in this context has increased over the years, with some studies placing the survival rate above 70%. These pregnancies are not exempt from both maternal and foetal complications, and so their management requires the joint efforts of nephrologists, gynaecologists, nurses, and nutritionists. Currently, we have been unable to establish consistent systematic treatment from both nephrological and gynaecological specialists in these patients. The main changes that need to be made are: increased time on dialysis, maintaining low levels of pre-dialysis urea, avoiding: maternal hypertension and hypotension, anaemia, urinary tract infections, and fluctuations in electrolytes. Adequate foetal monitoring is also necessary.


Asunto(s)
Fallo Renal Crónico/terapia , Complicaciones del Embarazo/terapia , Diálisis Renal , Anemia/etiología , Anemia/prevención & control , Nitrógeno de la Urea Sanguínea , Manejo de Caso , Parto Obstétrico/métodos , Femenino , Enfermedades Fetales/etiología , Enfermedades Fetales/prevención & control , Monitoreo Fetal , Soluciones para Hemodiálisis , Humanos , Hipertensión Inducida en el Embarazo/tratamiento farmacológico , Hipertensión Inducida en el Embarazo/etiología , Hipertensión Inducida en el Embarazo/prevención & control , Hipertensión Renal/complicaciones , Recién Nacido , Desnutrición/etiología , Desnutrición/prevención & control , Membranas Artificiales , Polihidramnios/etiología , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/prevención & control , Resultado del Embarazo , Embarazo de Alto Riesgo , Atención Prenatal , Diálisis Renal/efectos adversos , Diálisis Renal/instrumentación , Diálisis Renal/métodos , Tasa de Supervivencia
16.
Transplant Proc ; 41(6): 2104-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19715844

RESUMEN

INTRODUCTION: The clinical utility of predose levels of mycophenolic acid (MPA) monitoring among patients treated with mycophenolate mofetil (MMF) has been questioned. The aim of this study was to evaluate the impact of adequate MPA levels in the incidence of acute rejection episodes among a cohort of kidney transplant recipients. MATERIAL AND METHODS: In this retrospective study of 314 consecutive cases treated with tacrolimus, MMF, and steroids, evaluated 12-hour trough MPA samples during the first week as well as at 1, 3, 6, and 12 months as median values. RESULTS: During the first week, the median values of MPA were 1.6 microg/mL (p25-75 0.7-2.7 microg/mL) on mean doses of 1.84 +/- 0.38 g/d. The incidence of acute rejection was 28%. The mean MPA levels during the first week were significantly lower among patients who developed rejection than in nonrejectors (1.5 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P < .001). There were no significant differences in trough tacrolimus levels between rejectors and nonrejectors (11.2 +/- 0.4 vs 11.6 +/- 1.2 microg/mL; P < .78). Logistic regression analysis showed that one of the predictive factors of acute rejection was a 12-hour trough MPA <1.6 microg/mL (relative risk [RR] 2.6; CI [confidence interval] 95% 1.6-4.3; P < .001). CONCLUSIONS: Adequate MPA exposure is important to prevent acute rejection. Taking into account that the routine measurement of the area under the curve of MPA is impractical, at least the follow-up of trough MPA levels may help in the management of renal transplant recipients.


Asunto(s)
Rechazo de Injerto/epidemiología , Inmunosupresores/uso terapéutico , Trasplante de Riñón/inmunología , Ácido Micofenólico/uso terapéutico , Enfermedad Aguda , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/farmacocinética , Incidencia , Trasplante de Riñón/patología , Ácido Micofenólico/farmacocinética , Estudios Retrospectivos
17.
Transplant Proc ; 41(6): 2102-3, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19715843

RESUMEN

BACKGROUND: Large inter- and intrapatient variabilities have been observed in the pharmacokinetics of mycophenolic acid (MPA). As a consequence, the efficacy and safety of mycophenolate mofetil (MMF) may be optimized with individualized doses based on therapeutic drug monitoring. MATERIALS AND METHODS: In this retrospective study we analyzed; 7536 12-hour trough MPA samples obtained during the first year posttransplantation among 314 kidney recipients treated with tacrolimus, MMF, and corticosteroids. RESULTS: Despite taking similar MMF doses, patients with delayed graft function (DGF) showed lower 12-hour trough MPA levels than patients without DGF 1.4 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P = .001). There was a significant correlation between 12-hour trough MPA levels and creatinine clearance (r = .32; P < .001). Logistic regression analysis showed that creatinine clearance was a predictive factor of adequate 12-hour trough MPA levels (>1.6 microg/mL) at 7 days posttransplantation. Twelve-hour trough MPA levels at 7 days posttransplantation were lower among patients who developed an acute rejecton episode (1.5 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P < .001), whereas those with gastrointestinal side effects showed high levels (4.1 +/- 0.5 microg/mL). CONCLUSIONS: In patients with delayed or poor graft function, MMF doses greater than 2 g/d may be necessary to achieve adequate MPA levels. Therapeutic drug monitoring of MPA may be useful to prevent acute rejection episodes or toxicity.


Asunto(s)
Trasplante de Riñón/fisiología , Ácido Micofenólico/farmacocinética , Antibióticos Antineoplásicos/sangre , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapéutico , Monitoreo de Drogas/métodos , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Rechazo de Injerto/prevención & control , Humanos , Ácido Micofenólico/sangre , Ácido Micofenólico/uso terapéutico , Estudios Retrospectivos
18.
Chaos ; 18(1): 015104, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18377085

RESUMEN

Faraday waves near onset in an elliptical container are described by a third-order system of ordinary differential equations with characteristic slow-fast structure. These equations describe the interaction of standing waves with a weakly damped streaming flow driven by Reynolds stresses in boundary layers at the free surface and the rigid walls, and capture the proliferation with decreasing damping of periodic and nonperiodic relaxation oscillations observed near onset in previous simulations. These structures are the result of slow drift through symmetry-related Hopf bifurcations.

19.
J Exp Zool A Ecol Genet Physiol ; 309(1): 25-34, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18030681

RESUMEN

Here, we study a cycle of long-term starvation followed by refeeding in relation to the kinetics of serine dehydratase (SerDH) and tyrosine aminotransferase (TyrAT) in rainbow trout (Oncorhynchus mykiss). We determine SerDH- and TyrAT- specific activity at different substrate concentrations in liver and white muscle of juvenile trout starved for 70 days and then refed for 6 hr, 32 hr, 4 days, and 9 days. SerDH showed a hyperbolic kinetic with a K(m) for L-serine of 77.07+/-8.78 mM in the liver of control trout. After 70 days of starvation, the SerDH activity at saturate substrate concentration rose 100% over control. No significant changes were found in the K(m) values of the enzyme. After refeeding, the SerDH activity declined to control values. TyrAT also showed a hyperbolic kinetic with a K(m) for L-tyrosine of 1.86+/-0.12 and 2.55+/-0.57 mM in liver and white muscle, respectively. In starved trout, TyrAT activity in liver and white muscle was about 64 and 267%, respectively, higher than control. After 9 days of refeeding, the control values recovered, although, at 6 hr of refeeding, hepatic TyrAT activity was higher than that for starvation. This work shows that SerDH and TyrAT are present in rainbow trout and that the two enzymes have regulatory functions in the catabolism of their respective amino acids in this species.


Asunto(s)
L-Serina Deshidratasa/metabolismo , Oncorhynchus mykiss/metabolismo , Inanición/enzimología , Tirosina Transaminasa/metabolismo , Animales , Peso Corporal , Alimentos , Hígado , Músculo Esquelético , Tamaño de los Órganos , Factores de Tiempo
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